Research On The Hardening Mechanism Of 304/Q245R Explosive Welding Interface

304/Q245 R composite plate by explosive welding with the cladding plate corrosion, heat resistance and base metal high strength performance, compared with the other plate, no matter in material savings or in terms of performance, there is a lot of advantages, has been widely used in pressure vessels equipment manufacturing.This article mainly aims at 304/Q245 R composite plate by explosive welding bond interface, by using metallurgical microscope, Scanning electron microscopy(SEM), Electron Back Scattered Diffraction(EBSD), Energy Dispersive Spectrometer(EDS), Nano indentation and Electrochemical corrosion testing methods, To study the bond interface morphology, the way of bond interface, explosion welding defects, element distribution, the different zones hardness and corrosion resistance, analysis in bond interface different organizational structures distribution in deformation zone effect on the hardness and corrosion resistance.The results showed that: composite plate by explosive welding has waveform bond interface, average wave height 250.0μm, wavelength 900.0μm; Base metal side bond interface is divided into fine grain zone, fiber zone and distorted grain zone, Width respectively 18~23μm, 37~47μm and 90~100μm, grain size respectively 13.4, 9.9 and 8.6.In the same waveform cycle, existence two kinds of combination way direct combination and melting layer combination, directly combination interface diffusion phenomenon is not obvious, melting layer combination with internal involved in broken Q245 R metal particles, find Cr element diffusion phenomenon, Diffusion distance is less than 5μm; Vortices organization exists in bond interface, its internal exists incomplete fusion, inclusions, cracks and shrinkage defects, etc; Q245 R side fine grain zone and 304 side "white band" are the annealing recrystallization organization, the rest of the deformation area have been varying degrees of recovery; bond interface zone grain orientation different in base metal side, but fiber zone has deformation texture.Base metal Q245 R side, the hardness of pearlite in fiber zone, distorted grain zone and original grain zone respectively 3.34GPa、4.17 GPa and 3.68 GPa. After annealing treatment, Fiber zone pearlite occurs age softening, distorted grain zone occurs age hardening, and deformation ferrite does not fully recover during annealing process, keep high hardness; cladding metal 304 side deformation zone hardness at 20 μm from the interface has a maximum value, 6.40 GPa, the result of joint action by deformation hardening and deformation martensite; Composite plate bond interface corrosion resistance is lower than the plate 304, and higher than Q245 R, Satisfy the engineering application.